Tai Lin Wu (Jack Wu)

Tai Lin Wu (Jack Wu)

There are no shortcuts to any place worth going.

← Design Patterns

Iterator Pattern

Published:

Iterator is a behavioral design pattern that lets you traverse elements of a collection without exposing its underlying representation (list, stack, tree, etc.).

Scenario

Collections are one of the most used data types in programming. Nonetheless, a collection is just a container for a group of objects.

collection traversal

Adding more and more traversal algorithms to the collection gradually blurs its primary responsibility, which is efficient data storage.

iterator

without iterator pattern:

A position:

  • plan1: next is B
  • plan2: next is C

with iterator pattern:

  • plan1: A->B->C->…
  • plan2: A->C->…

Structure

structure

Case Study

https://refactoring.guru/design-patterns/iterator/cpp/example